4.3Authentication: what you should know in 2026

This is worth knowing because the current connector changed very recently.

Salesforce Connector 12.0.0 was released July 21, 2026, requires Java 17, and removed its OAuth Username Password connection type because Salesforce is retiring that flow. MuleSoft currently points users toward alternatives including OAuth 2.0, Client Credentials, JWT, and SAML.

For machine-to-machine Mule integrations, the two patterns I'd especially recognize are:

OAuth Client Credentials

OAuth JWT

Client Credentials

Think:

Mule application
     ↓
client ID + client secret
     ↓
Salesforce
     ↓
access token

No interactive human login.

Client Credentials is specifically designed for applications acting on their own behalf, making it appropriate for machine-to-machine scenarios.

JWT

Conceptually:

Mule
 ↓
signed JWT assertion
 ↓
Salesforce OAuth endpoint
 ↓
access token

This avoids storing a Salesforce user's plaintext password.

Interview answer

If asked:

“How would you authenticate MuleSoft to Salesforce?”

I'd say:

“For a new server-to-server integration I'd expect OAuth-based authentication, commonly Client Credentials or JWT depending on the organization's Salesforce security model. I would keep credentials outside the Mule XML and externalize secrets by environment.”

That is enough unless the role specifically expects Salesforce identity expertise.